Which of these processes is least associated with producing genetic abnormalities? a) deletion b) nondisjunction c) replication d) transformation

The answer is (C) Replication

Though occasional errors could occur in cells during replication; the cells have error checking and proofing mechanisms that reduce the rate of error to one to several million replications in higher eukaryotes.
After all, one mismatch error during replication would not result in major effects. The others choices, however, have higher rates of causing genetic abnormalities.